Before carbonaceous material is gasified, it generally undergoes pyrolysis which yields liquids, gases, and a solid low H/C material referred to as char. The char can be gasified in the presence of steam to produce CO and H.sub.2. If carbonaceous material is used which has a tendency to agglomerate, such as bituminous coals, agglomeration of the carbonaceous material can result during pyrolysis. This is undesirable because of its adverse effects on conventional reactor designs. For example, in fluidized beds, the agglomerated material results in particles too large to fluidize, and in fixed beds, agglomeration can cause the bed to plug.
Attempts to decrease agglomeration include treating the material with basic compounds of alkali and alkaline-earth metals. Furthermore, the treatment of carbonaceous materials, in general, with such compounds enhances the rate of subsequent gasification of char resulting from pyrolysis. While such compounds reduce agglomeration tendency and enhance gasification of the char, they could have a detrimental effect on the production of liquids during pyrolysis. For example, if the pyrolysis is conducted at about atmospheric pressure, relatively low liquid yields result.
Consequently, there is a need in the art for a process for pyrolyzing carbonaceous materials to obtain relatively high liquid yields, followed by gasifying the resulting non-agglomerated char.